content: /**
   * Copyright (c) 2016-present, RxJava Contributors.
   *
   * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in
   * compliance with the License. You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software distributed under the License is
   * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See
   * the License for the specific language governing permissions and limitations under the License.
   */
  
  package io.reactivex.flowable.internal.operators;
  
  import org.reactivestreams.Subscriber;
  
  import hu.akarnokd.reactivestreams.extensions.ConditionalSubscriber;
  import io.reactivex.common.annotations.Nullable;
  import io.reactivex.common.functions.*;
  import io.reactivex.flowable.Flowable;
  import io.reactivex.flowable.internal.subscribers.*;
  
  public final class FlowableDistinctUntilChanged<T, K> extends AbstractFlowableWithUpstream<T, T> {
  
      final Function<? super T, K> keySelector;
  
      final BiPredicate<? super K, ? super K> comparer;
  
      public FlowableDistinctUntilChanged(Flowable<T> source, Function<? super T, K> keySelector, BiPredicate<? super K, ? super K> comparer) {
          super(source);
          this.keySelector = keySelector;
          this.comparer = comparer;
      }
  
      @Override
      protected void subscribeActual(Subscriber<? super T> s) {
          if (s instanceof ConditionalSubscriber) {
              ConditionalSubscriber<? super T> cs = (ConditionalSubscriber<? super T>) s;
              source.subscribe(new DistinctUntilChangedConditionalSubscriber<T, K>(cs, keySelector, comparer));
          } else {
              source.subscribe(new DistinctUntilChangedSubscriber<T, K>(s, keySelector, comparer));
          }
      }
  
      static final class DistinctUntilChangedSubscriber<T, K> extends BasicFuseableSubscriber<T, T>
      implements ConditionalSubscriber<T> {
  
  
          final Function<? super T, K> keySelector;
  
          final BiPredicate<? super K, ? super K> comparer;
  
          K last;
  
          boolean hasValue;
  
          DistinctUntilChangedSubscriber(Subscriber<? super T> actual,
                  Function<? super T, K> keySelector,
                  BiPredicate<? super K, ? super K> comparer) {
              super(actual);
              this.keySelector = keySelector;
              this.comparer = comparer;
          }
  
          @Override
          public void onNext(T t) {
              if (!tryOnNext(t)) {
                  s.request(1);
              }
          }
  
          @Override
          public boolean tryOnNext(T t) {
              if (done) {
                  return false;
              }
              if (sourceMode != NONE) {
                  actual.onNext(t);
                  return true;
              }
  
              K key;
  
              try {
                  key = keySelector.apply(t);
                  if (hasValue) {
                      boolean equal = comparer.test(last, key);
                      last = key;
                      if (equal) {
                          return false;
                      }
                  } else {
                      hasValue = true;
                      last = key;
                  }
              } catch (Throwable ex) {
                 fail(ex);
                 return true;
              }
  
              actual.onNext(t);
              return true;
          }
  
          @Override
          public int requestFusion(int mode) {
              return transitiveBoundaryFusion(mode);
          }
  
          @Nullable
          @Override
          public T poll() throws Throwable {
              for (;;) {
                  T v = qs.poll();
                  if (v == null) {
                      return null;
                  }
                  K key = keySelector.apply(v);
                  if (!hasValue) {
                      hasValue = true;
                      last = key;
                      return v;
                  }
  
                  if (!comparer.test(last, key)) {
                      last = key;
                      return v;
                  }
                  last = key;
                  if (sourceMode != SYNC) {
                      s.request(1);
                  }
              }
          }
  
      }
  
      static final class DistinctUntilChangedConditionalSubscriber<T, K> extends BasicFuseableConditionalSubscriber<T, T> {
  
          final Function<? super T, K> keySelector;
  
          final BiPredicate<? super K, ? super K> comparer;
  
          K last;
  
          boolean hasValue;
  
          DistinctUntilChangedConditionalSubscriber(ConditionalSubscriber<? super T> actual,
                  Function<? super T, K> keySelector,
                  BiPredicate<? super K, ? super K> comparer) {
              super(actual);
              this.keySelector = keySelector;
              this.comparer = comparer;
          }
  
          @Override
          public void onNext(T t) {
              if (!tryOnNext(t)) {
                  s.request(1);
              }
          }
  
          @Override
          public boolean tryOnNext(T t) {
              if (done) {
                  return false;
              }
              if (sourceMode != NONE) {
                  return actual.tryOnNext(t);
              }
  
              K key;
  
              try {
                  key = keySelector.apply(t);
                  if (hasValue) {
                      boolean equal = comparer.test(last, key);
                      last = key;
                      if (equal) {
                          return false;
                      }
                  } else {
                      hasValue = true;
                      last = key;
                  }
              } catch (Throwable ex) {
                 fail(ex);
                 return true;
              }
  
              actual.onNext(t);
              return true;
          }
  
          @Override
          public int requestFusion(int mode) {
              return transitiveBoundaryFusion(mode);
          }
  
          @Nullable
          @Override
          public T poll() throws Throwable {
              for (;;) {
                  T v = qs.poll();
                  if (v == null) {
                      return null;
                  }
                  K key = keySelector.apply(v);
                  if (!hasValue) {
                      hasValue = true;
                      last = key;
                      return v;
                  }
  
                  if (!comparer.test(last, key)) {
                      last = key;
                      return v;
                  }
                  last = key;
                  if (sourceMode != SYNC) {
                      s.request(1);
                  }
              }
          }
  
      }
  }
  